Manufacture of steel.



WILLIAM R. WALKER or new irons, 3:. Y.

MANUFACTURE or: street.

1% Drawing.

To till to/mm it may concern:

Specification of Letters Patent.

Be it known that I, lVILLiAii R. WALKER, f a citizen of the United States, and a resident of the borough of Manhattan, city,

5 county, and State oi New York, have invented certain new and useful Improvements in the Manufacture of Steel, of which the following is a specification.

This invention relates to the use of electric furnaces in the manufacture of steel.

The principal purpose of the invention is to provide a eheap and rapid process for making steel of good quality from iron which may lie classified as to its phosphorus content between the grades commonly known as basic Bessemer iron and acid Bessemer iron. Basic Bessemer iron is that which is commonly blown in Bessemer converters with basic lining and slag, and is roughly from 1.80 per cent. to 2.20 per cent. or even a little higher in phosphorus. Acid Besseiner ii'on isth'at. which is ordinarily treated in Bessemer converters with acid lining and sing and contains under 0.12 per cent. of

phosphorus, ordinarily between 0.05 per cent. and 0.10 per cent. Iron which in plies plioi'lis content is between these two classes usiially'coiitains too little phosphorus for use in the basic Bessemer converter, and

'contains too much phosphorus to make it available in the acid converter, it is, there fore, treated in the basic open-hearth where, by the necessary additions, its coitltent of phosphorus can he reduced to practically any desired point. The present process is designed especially to facilitate the making of steel from this intermediate grade of iron, and is at the same time adapted for use with iron of lower phosphorus content.

A process embodying the invention is as follows; Iron of the stated phosphorus contentis first partially blown in the acid con vertcrs sullicient to remove the silicon and. a portion of the c rhon. The iron in question has suflicient heat-giving elements for thispartial blow. The iron is only slightly oxidized by this partial blow. The partially blown metal is then transferred,ordinarily by means of a ladle, to an intermediate mixer at in the'forin of a basic open-hearth vfurnace of suliioi'eiit capacity. to hring,abont substantial uniformity in the products oi the several converters and to carry always a siipply of hot metal for the subseqnenttreat- 15 nient iii the electric furnaces hereinafter referred to. The minor is basic lined, is heatready for the electric furnaces so that inn Faten'ted Fee. 1%, it 91 1.

Application filed May 4, 1911. Serial No. 825,061.

ed by gas and ail with the aid. of rt enerators in the well-known manner of openhearths and is supplied with a basic slag of iron ore and lime, or the like, to reduce the phosphorus con bet to the point desired in the final product. in this open ion a portion or. any sliltiir present is incidentally removed and there is a further oxidation. of the iron present.

From time to tinie portions of the metal in the intermediate mixer transferred to electric furnaces. The use of the miner provides a supply of molten always G medi'at'ely after pouring a finished eiarge 7 therefrom a new charge may he introduced. As the electric furnace is witlioii l means when e?"pty, and. cools very r and the costoft' heating it is eonsidc saving of time between heats is of Sun tial importance. In the electric inn cs 51 non-oxidizing atmosphere is main 2. These furnaces for examp e may of t e Her-(sun are type. By reason of the p vions operations iipon the meta 111g may he used for the else it: -urns which means a substantial so ug in er ipe both first cost and repairs and other i ating costs, and a more rapid. ojert i or larger tonnage per day amateurs ohtained with a basic lining. The ti" em in the electric furnace isr'efei'red to more detail hereinafter.

The metal from the electric furnaces "1 transferred to a final min-e whieh in: :1 ladle of large capacity wi acid l and with or without electrodes o heatihg means. it. substantial q molten metal is maintained in mixer so as to obtain. a product tially uniform in carbon and other cuts. The refined steel prod.

final mixer is then cast either directly th from or lay-transferring it first to a more 1011 convenient smaller casting ladle.

Subsequently to the dephosphoriz' '1 the metal in theinterinediate mixer, s to say either in the electric 1" 1 final mixer, or partly in one and p n the other, deoxidi the metal. By r tute and n'oiroxi. inna nospliere electric fiir'na'ce and the ox theinetal in the final mixer these we el's serves to higl and eliminate the microscopic sl 251 additions are stage of the process subsequent to the do phosphorization, the treatment in the electric furnaces and in the final mixer serving to refine the steel and to eliminate microscopic slag, and casting the refined steel proi the final product, taking metal from said mixer from time to time to acid electric furnaces and treating it therein, and transferring the metal from said electric furnaces to a mixer where it undergoes refinement and elimination of microscopic slag and the steel is maintained substantially uniform in carhon and other ingredients and casting such steel.

having a phosphorus content below that of basic Bessemer iron, the process which consists in partially blowing the same in an acid converter, treating the partially blown 3. In the manufacture of steel from iron metal from said converter in an intermediate mixer with a bas c slag to reduce the phosphorus content to the point desired in the final product,v taking metal from said mixer from time to time to an acid electric furnace and deoxidizing it therein.

4. In-the manufacture of steel from ironv having a phosphorus content below that of basic Bessemer iron, the process which consists in blowing the same in an acid converter to eliminate silicon and carbon, subsequently reducing the phosphorus content to the point desired in the final product and thereafter deoxidizing in an acid electric furnace the previously dephosphorized metal.

5. In the manufacture of steel the process which consists in eliminating silicon and carbon in an acid converter, subsequently reducing the phosphorus content to the point desired in the final product and thereafter deoxidizing in an acid electric furnace.

In witness whereof, I have hereunto I signed my name 111 the presence of two sub scribing Witnesses.

' WILLIAM R. \VALKER Vitnesses I D. ANTHONY Usma, H. CLAY RnIMEI-c 

